1. Field of the Invention
The present invention relates to a surface scan measuring device, a surface scan measuring method, a surface scan measuring program, and a recording medium. More specifically, the present invention relates to, for example, a surface scan measuring device for measuring the form of the surface of a workpiece along with the roughness, the waviness, the contour and other surface texture of the workpiece,
2. Description of Related Art
Conventionally, a roughness measuring machine, a contour measuring machine, a roundness measuring machine, a coordinate measuring machine and the like are known as a measuring machine for measuring the surface texture and the three-dimensional profile of a workpiece by scanning the surface of the workpiece with a scanning probe (see, for example, Patent Document 1: Japanese Patent Application Laid-Open No. Hei. 5-248852, Patent Document 2: Japanese Patent Laid-Open Publication No. Hei. 8-178646, Patent Document 3: Japanese Patent Laid-Open Publication No. 2000-39302, and Patent Document 4: Japanese Patent Laid-Open Publication No. 2003-202219).
For example, a known measuring system that utilizes a coordinate measuring machine is configured so as to include a coordinate measuring machine adapted to move a scanning probe, a joystick to be operated manually, a motion controller for controlling the operation of the coordinate measuring machine and a host computer for operating the coordinate measuring machine by way of the motion controller and processing the measurement data acquired by the coordinate measuring machine to determine the dimensions and the form of a workpiece. The moving speed of the scanning probe and the sampling pitch of the measurement data and other necessary parameters are defined and input to the host computer in advance.
With the above-described arrangement, the scanning probe scans the surface of the workpiece at the preset moving speed to acquire measurement data at a preset sampling pitch under the control of the motion controller and the host computer. The form of the workpiece is analyzed on the basis of the measurement data.
However, when the moving speed for moving the scanning probe and the sampling pitch for acquiring measurement data are fixed to predefined respective values, there arises a problem that the moving speed and the sampling pitch can be inadequate for scanning the surface of the workpiece depending on the surface condition of the workpiece. For example, if the surface of the workpiece shows undulations only to a small extent and the scanning speed is fixed to a low value, it will take an unnecessarily long time for the surface measurement. Conversely, if the surface of the workpiece shows undulations to a large extent and the scanning speed is fixed to a high value, there may arise errors such as excessive push-in and breakaway. Additionally, excessive data can be acquired if the surface of the workpiece shows undulations to a small extent and data are collected at a fixed sampling pitch, whereas the acquired data may be insufficient for measuring the surface if the surface of the workpiece shows undulations to a large extent and data are acquired at a preset and fixed sampling pitch.